Solve the system of equations below.

Question

-5y+3x=-16

10y+4x=62

What is the x-value in the solution?

A. 3

B.4.6

C. 5

D. 6.6

 

I can't grasp the idea of how to solve this. Any advice helps. Thanks!

Answer 1

-5y + 3x = -16           eq1
10y + 4x = 62            eq2

 

 

Multiply eq1 by 2.  Keep eq2 the same.

 

-10y + 6x = -32          

10y + 4x = 62

 

 

Next, we can add the equations together to eliminate the y terms.  We end up with

 

10x = 30

 

I will let you finish off from here.

 

Something extra I want to tell you so that you can get ahead in these types of problems.  If you are asked to solve for both x and y, approach it the same way to solve for one variable.  Once you have solved that variable, substitute it into one of the equations that was not manipulated to solve for the other variable.

 

Answer 2

You need to multiply one of the equations with a number which will help you eliminate one of the variables during solving simultaneously. Her, its better to multiply the first equation by 2(it becomes -10y + 6x = -32). Then solve simultaneously or substitute the value of y.